Prior art measuring and indicating devices commonly include support means adapted to be attached to a ski and a wheel rotatably supported by the support means so as to be positioned in rolling contact with snow underlying the ski. The wheel is thereby caused to rotate as the ski is moved across the underlying snow. These prior art devices also include indicating means associated with the wheel and responsive to the rotations thereof for calculating or measuring a predetermined characteristic of the skier's travel, such as speed or distance, as the ski moves across the snow. Furthermore, such devices also include display means associated with the indicator means for displaying the calculated characteristic. Examples of such devices are shown and described in U.S. Pat. No. 4,546,650, 3,505,878 and 4,262,537.
A limitation associated with devices such as those described in the referenced patents relate to the viewability by the skier of the calculated characteristic. For example, each device described in the referenced patents includes display means mounted directly to the ski thus requiring the skier to look down at his skis and away from his normal, or forwardly-directed, line of vision in order to observe the display means. If the skier is moving at a relatively high rate of speed for a period of time, any such observance of the display means during that period may be inconvenient or dangerous.
Furthermore, inasmuch as each device described in the referenced patents is carried directly by the skis to which the device is attached, each component of the device is exposed to shock effects associated with any jolting of the skis if, for example, the skis are moved rapidly across relatively rough terrain or otherwise suddenly strike the ground from an elevated condition. If the components of the device possess a low resistance to shock, damage to the components or a reduction in the useful life of the device is likely to result therefrom.
Another limitation associated with each device described in the referenced patents relates to its inability to accurately measure the predetermined characteristic of travel if the skier's skis occasionally move off of, or become elevated above the snow during use. Such an inability is believed to be due, at least in part, to the relatively rigid attachment of the rotatable wheel to the ski preventing the wheel from making contact with the snow when the ski is elevated thereabove. Unless, of course, the wheel makes rolling contact with the snow, the wheel will not rotate in accordance with the movement of the ski, and errors in the calculated characteristics are likely to result therefrom.